The use of an electronic lock has been growing more and more in locking doors-because its action is more accruate than other locks, and it is more difficult to break it. Opening an electronic lock requires the use of a special card which has an invisible coded number on it, which card is to be checked by the lock to determine whether the coded number is the right one for the lock before opening. At the same time, it can also be controlled in its use combined with a computer system. Therefore, it is more suitable for a large building like a hospital, a large hotel, but not so convenient for a common living house.